1. Field of the Invention
The present invention relates to an engine mount for a vehicle or ship, more specifically, an engine mount comprising a vibration side attaching member to be attached to an engine, a supporting side attaching substrate to be attached to a supporting frame, and a rubber vibration isolator which couples these components and prevents vibrations of the engine, wherein the vibration side attaching member penetrates the rubber vibration isolator and mainly serves as a stopper at the compression side in conjunction with the supporting frame.
2. Description of the Related Art
In a case where the body of a vehicle or a ship is installed with an engine which is a vibration generator, an engine mount is interposed between them to deaden vibrations of the engine and prevent vibrations from being directly transmitted to the body of the vehicle or ship. As an example of such a type of engine mount, engine mounts disclosed in Japanese Unexamined Patent Publications No. H08-277878 and No. H09-25983 (shown in FIG. 8 and FIG. 9) are generally known. The engine mount a of FIG. 8 has a vibration side attaching member b to be attached to an engine and a supporting side attaching substrate c to be attached to the body of a ship or vehicle, and a vibration deadening mechanism d is installed between them. In this vibration deadening mechanism d, a partition i partitions a main liquid chamber f including a wall surface made from a thick rubber vibration isolator e and a sub liquid chamber h including a wall surface made from a thin rubber film g, the main liquid chamber f and the sub liquid chamber h are communicated with each other by an orifice j, and a plurality of foams k that contain a number of independent bubbles and have an action for absorbing the inner pressure of the main liquid chamber f are filled in the main liquid chamber f by changing the foaming magnification, whereby high-frequency small-amplitude vibrations are absorbed by the foam k1 with a high foaming magnification, and low-frequency large-amplitude vibrations are absorbed by the foam k2 with a low foaming magnification. In a case where great movement that may result in breakage of the vibration deadening mechanism d occurs, a stopper l installed at the engine side of the outside and a stopper m at the side of the body of a vehicle or ship cope with the great movement.
In the engine mount a1 of FIG. 9, the vibration side attaching member b and the supporting side attaching substrate c are coupled by a rubber vibration isolator e, a diaphragm n is provided inside the supporting side attaching substrate c to form a liquid sealing chamber o and comprises a partition to partition this liquid sealing chamber o into two liquid chambers communicated by the orifice j, the vibration side attaching member b is formed into a turned-down cup shape and covered on the rubber vibration isolator e by adhering the upper surface to the upper end portion of the rubber vibration isolator e without adhering the circumferential side surface on the upper end portion, the outer circumferential end portion of this vibration side attaching member b is extended outward to form a stopper m at the side of the body of a vehicle or ship, a stopper l of the engine side is formed above the vibration side attaching member b, and the supporting side attaching substrate c is extended upward between the stopper l and stopper m to form an inner flange p for stoppers, whereby in a case where great movement occurs, the entirety of the stopper l and stopper m comes into contact with the inner flange p to cope with the movement.
Although the abovementioned engine mount a absorbs high-frequency small-amplitude vibrations and low-frequency large-amplitude vibrations, if great movement that cannot be absorbed by the vibration deadening mechanism d occurs, the stopper l and stopper m installed at a part of the outside are not sufficient to cope with the movement.
On the other hand, in the engine mount a1, in a case where great movement occurs which cannot be absorbed by the vibration deadening mechanism including components such as the rubber vibration isolator e and liquid sealing chamber o, the entirety of the stopper l and stopper m comes into contact with the inner flange p, whereby vibrations exceeding the flange are prevented and breakage of the vibration deadening mechanism can be prevented. However, in the engine mount a1, the vibration deadening mechanism constructed so that the entirety of the stopper l and stopper m comes into contact with the inner flange p, that is, bulky vibration deadening mechanism is installed outside, so that the mechanism occupies a large space, and the number of parts tends to be large. Furthermore, since the stopper l and stopper m cope with great movement by coming into contact with the inner flange p between the stoppers, it is relatively difficult to reduce the range of movements, so that it cannot be said that durability of the rubber vibration isolator e is sufficient.